1. Field of the Invention
The present invention relates to a method of treating radioactive waste water generated at nuclear power facilities after chemical decontamination.
2. State of the Art
Radioactive waste water generated by decontamination contains, in addition to crud, a large amount of decontaminating agents. The decontaminating agents, containing formic acid, EDTA, citric acid, ascorbic acid, oxalic acid, and other organic acids, also normally contain organic inhibitors and surface active agents. Ultimately, the radioactive waste water is evaporated and concentrated, and the residue is solidified, but when decontaminating agents containing the previously mentioned organic acids are present, the properties of the concentrated solid are unfavorable affected, particularly the mechanical strength thereof. Therefore, before the evaporation and concentration process, it is necessary to remove these organic acids.
A method of decomposition by oxidation of organic materials in waste water using H.sub.2 O.sub.2 in the presence of iron ions is reported in "Chemical Removal of ABS from Water-water Effluents", Hugh R. Eisenhauer, JOURNAL WPCF, VOL. 37, No. 11, and the art of decomposing radioactive ion exchange resins is developed and disclosed in Japanese Patent Disclosures No. 58-72099 and No. 59-44700.
Also, a method of decomposing organic materials using at the same time ultraviolet rays and ozone is known ("OZONE/UV Process Effective Wastewater Treatment", H. W. Prengle, Hydrocarbon Processing, Oct. 1975, p. 82), and there have been attempts to apply this treatment to radioactive organic materials, in Japanese Patent Disclosures No. 58-52598 and No. 58-52599, and Japanese Patent Application No. 58-99847.
However, a method of treating radioactive waste water containing decontaminating agents comprising organic materials has not yet been established.